Perhaps I missed it, was looking just the other day for a chapter or even a paragraph with MVC advice. Did not see any 'this is what a controller is, why you use a controller and how Sencha advises you use this within your application'. Again, I saw mentions of MVC but only within the context of building an app at the end of the book and felt it was a passing thought by the authors.

Theres very good stuff in that book you'll not easily find on the web but I feel MVC should be a bit more prominent as it's not an easy concept for some to pickup on... especially considering how integral that concept is to building ST apps.